This invention relates to a press, particularly for compacting scrap metal for subsequent melting, e.g. in an electric furnace.
As is known, the feeding of metal scraps to an electric furnace for the melting of said scraps is carried out, according to a typical traditional process, by simply introducing basketfuls of scraps sequentially into the furnace. For each melting operation, three to six molten basketfuls of scraps are required one after the other. The disadvantages of this method are evident, in that the repeated opening of the furnace brings about a high rate of wasted heat as well as considerable loss of time, before the melting operation is completed. However, such feeding is made necessary by the fact that the material poured from each basket into the furnace, owing to its uncompressed state, substantially fills the whole space inside the furnace and makes it impossible to add to the feed until it has been substantially molten.
In order to obviate such drawbacks, an improved method has been proposed of feeding scraps to electric furnaces. According to this method, provision is made for the scraps to enter the furnace after they have been compacted and pressed in a cavity or recess which has substantially the same inside dimensions as the furnace. In other words, the scraps are put first into a cavity or depression formed directly in the floor or within a movable container, and then squeezed and pressed against the cavity bottom to result in a compacted layer. The cavity is next refilled with more scraps which are once again compressed to produce a further layer overlying the former. The process goes on until said cavity is filled up to a desired level. The scraps are then removed, e.g. by means of rope systems or engaging means prearranged inside the chamber, and introduced into the melting furnace.
It will be apparent how this approach, while better than the previous one, since it allows for a substantial filling of the electric furnace with a single batch or pack of scraps, is not entirely devoid of some important disadvantages. For example, the scraps put into the cavity must be selected in advance, because it is obviously impossible to fit in the cavity any elements exceeding the cavity own dimensions. Another drawback is to be found in that the numerous passes required to fill such a compression cavity with successive layers involve a considerable loss of time. Furthermore, the compacted scrap pack, resulting from superimposed layers which are substantially independent of one another, is difficult to handle and susceptible to easily separate at the layers themselves.